MARINE BIOPRODUCTION FACILITY

Abstract

A marine bioproduction facility for farming of sessile marine organisms in a body of water is disclosed. The facility comprises an array of at least two production modules in contiguous geometrical relationship to each other, where each of the at least two production modules is adapted to be arranged within a vertical column with a predefined horizontal cross section and extending downwards from the water surface, where at least one of the at least two production modules comprises at least one growth surface for sessile marine organisms, and an upper part comprising at least one opening adapted to allow access to the vertical column. Further, a method for growth and harvesting of marine sessile organisms using the marine bioproduction facility is presented.

Claims

1. A marine bioproduction facility for farming of sessile marine organisms in a body of water with a water surface, wherein the facility comprises at least one cluster, where each cluster comprises at least two production modules, where the production modules of each cluster are arranged side by side in a 2 dimensional scalable and selectable pattern, where each of the at least two production modules is adapted to be operated independently of the other production modules, being confined within a vertical column with a pre-defined horizontal cross section and extending downwards from the water surface, where at least one of the at least two production modules comprises at least one growth surface for sessile marine organisms, and where each of the at least two production modules comprises an upper part where the upper part comprises at least one opening adapted to allow individual access to the vertical column in which the production module is arranged, and where the upper part of at least one production module comprises a ring structure around the opening and has a positive buoyancy in water, and where an outer circumference of the ring structure has one of the following shapes: polygonal, circular and elliptic, and where the at least one production module comprises fixture and suspension means for attachment, deployment, and recovery of the at least one growth surface for sessile marine organisms.

2. A marine bioproduction facility according to claim 1, where the fixture and suspension means comprises a mounting fixture arranged on the upper part, where the at least one growth surface is connected to the mounting fixture, and the mounting fixture is adapted to paying out and suspending the at least one growth surface.

3. A marine bioproduction facility according to claim 1, further comprising guiding means for keeping the at least one growth surface within the corresponding vertical column.

4. A marine bioproduction facility according to claim 3, where the guiding means comprises a weight connected to the growth surface, for extending the at least one growth surface.

5. A marine bioproduction facility according to claim 1, where at least one of the at least two production modules comprises at least one of the following: a tank with a tank volume, and technical equipment.

6. A marine bioproduction facility according to claim 1, where at least one production module comprises a lower part adapted to be arranged below the upper part.

7. A marine bioproduction facility according to claim 3, where the guiding means comprises a retaining fixture arranged on the lower part, the retaining fixture comprising a guiding ring for the at least one growth surface.

8. A marine bioproduction facility according to claim 3, where the growth surface is connected at the lower end to a cable which passes via a retaining fixture arranged on the lower part and returns to a take-up fixture on the upper part.

9. Marine bioproduction facility according to claim 6, where the lower part of at least one production module comprises a ring structure, where an outer circumference of the ring structure has one of the following shapes: polygonal, circular and elliptic.

10. A marine bioproduction facility according to claim 9, where the guiding means comprises the ring structure of the lower part, and the at least one growth surface or a cable connected thereto, passes through said ring structure.

11. Marine bioproduction facility according to claim 6, where the lower part has a negative buoyancy in water.

12. Marine bioproduction facility according to claim 3, where the fixture and suspension means are arranged on the upper and lower parts of a given production module, and the suspension means are arranged between the upper and lower parts, where the fixture and suspension means are adapted to stretch the at least one growth surface between the upper and lower parts, and for deploying and retrieving the at least one growth surface through the opening in the upper part.

13. Marine bioproduction facility according to claim 1, where at least one growth surface for sessile organisms is at least one of the following: sectioned as a function of depth in the vertical column, and formed as a helical strip adapted to be rotated about its vertical axis for causing movement of water in the body of water.

14. Marine bioproduction facility according to claim 5, where the tank volume can be accessed via the opening of the corresponding upper part.

15. Marine bioproduction facility according to claim 1, where the 2 dimensional scalable and selectable pattern is one of the following: random, serpentine, linear, triangular, square, and hexagonal close-packed (HCP).

16. Marine bioproduction facility according to claim 1, where the at least one cluster has a polygon shaped circumference having one of the following shapes: triangle, square, rectangle, pentagon, hexagon.

17. Marine bioproduction facility according to claim 1, where each production module is mechanically linked to at least one neighboring production module.

18. Marine bioproduction facility according to claim 1, comprising an upper floor arranged to be floating at or near the surface of the body of water, where the upper floor comprises the upper parts of at least two production modules.

19. Marine bioproduction facility according to claim 18, where the upper floor comprises buoyancy modules for providing buoyancy to the upper floor.

20. Marine bioproduction facility according to claim 7, comprising a lower floor arranged to be submerged in the body of water, where the lower floor comprises the lower parts of at least two production modules.

21. Marine bioproduction facility according to claim 14, where the facility further comprises a sub-floor arranged below the at least one cluster, and the sub-floor is arranged for one or more of the following: collecting waste products, providing a habitat for bottom-living organisms, and increasing the structural strength of the facility.

22. Marine bioproduction facility according to claim 21, where the sub-floor is one of the following: i) A mechanically stiff platform of annuli, tanks or cylinders linked side by side and adapted for carrying collection surfaces, and ii) A sheet suspended below the cluster.

23. Marine bioproduction facility according to claim 14, where the facility further comprises a roof structure arranged above the at least one cluster, and where the roof structure is arranged for providing one or more of the following: environmental protection, a platform for technical installations, an area for growing light dependent cultures, and a solar power collector.

24. Marine bioproduction facility according to claim 1, where each of the at least two production modules has a unique production module address identifying its location in the facility.

25. Marine bioproduction facility according to claim 1, where at least one growth surface is sectioned according to claim 12, where each section has a unique section address identifying its location in the corresponding production module.

26. Marine bioproduction facility according to claim 23, where the at least one cluster has a unique cluster address identifying its location in the facility.

27. Marine bioproduction facility according to claim 14, where the facility comprises a perimeter structure at least partly surrounding at least one of the clusters.

28. Marine bioproduction facility according to claim 27, where the perimeter structure is one of the following: a linked structure adapted to float and surround the cluster in two dimensions, a closed barrier structure adapted to envelop the cluster partly or completely in the water.

29. Marine bioproduction facility according to claim 1, where the facility comprises at least one macroscale structure, where the macroscale structure comprises at least two clusters, where the at least two clusters are mechanically linked.

30. Marine bioproduction facility according to claim 29, where the at least one macroscale structure comprises at least one cluster with a polygon shaped circumference.

31. Marine bioproduction facility according to claim 29, where the at least one macroscale structure comprises two or more triangular clusters.

32. Marine bioproduction facility according to claim 1, where at least one side of the polygonal cluster is closed to surrounding water by a barrier comprising one or more of the following: A number of closed production modules in the shape of cylindrical tanks linked side by side, and a sheet or curtain.

33. Marine bioproduction facility according to claim 31, where the at least one macroscale structure comprises at least two triangular clusters arranged such that the closed sides of the at least two polygonal clusters connect to form an extended closed barrier.

34. A method for growth and harvesting of marine sessile organisms using a marine bioproduction facility according to claim 1, comprising the steps of: defining actions according to a schedule pertaining to a production module, exposing the upper part of the production module in preparation for insertion of a growth surface, inserting a growth surface into the production module through the opening in its upper part, connecting the growth surface to fixtures on the upper part of the production module, incubating the growth surface in the production module for an incubation period, extracting the growth surface from the production module by pulling it up through the opening in its upper part, removing and collecting biomass from the growth surface.

35. Method for growth and harvesting of marine sessile organisms according to claim 34, comprising before the step of exposing the upper part, the additional steps of: identifying a physical location of one or more of the following: i) the cluster, using the cluster address, ii) a production module using the production module address, and iii) a growth surface section using the section address.

36. Method for growth and harvesting of marine sessile organisms according to claim 34, where the removing and collecting of biomass from the growth surface is performed by one or more of the following processes: scraping, brushing, blowing, suction, shaking, and beating.

37. Method for growth and harvesting of marine sessile organisms according to claim 34, comprising, before the step of incubating the growth surface, the additional steps of: connecting the growth surface to fixtures on the lower part of the production module, and stretching the growth surface between the upper and lower parts on the production module.

38. Method for growth and harvesting of marine sessile organisms according to claim 34, comprising the step of pre-seeding the growth surface with larvae or juveniles of the sessile marine organisms before inserting it into the production module.

39. Method for growth and harvesting of marine sessile organisms according to claim 34, where at least one of the steps is performed by automated equipment.

40. Method for growth and harvesting of marine sessile organisms using a marine bioproduction facility according to claim 35, where at least one of the steps is performed by a mobile robot.

41. Method for growth and harvesting of marine sessile organisms according to claim 34, comprising the step of covering the upper part of one or more production modules by a removable light tight lid, shroud, tarp or housing, for protection from light during the incubation period.

Description

SHORT DESCRIPTION OF THE FIGURES

[0063] FIGS. 1a,b,c,d,e,f disclose six versions of a production module.

[0064] FIG. 2 discloses a deployed production module.

[0065] FIGS. 3a,b,c,d,e disclose a growth and harvesting cycle in a production module.

[0066] FIG. 4 discloses a linear cluster of production modules being tended by a tending/harvesting machine.

[0067] FIG. 5 discloses a triangular cluster of production modules with circular horizontal footprints.

[0068] FIGS. 6a,b,c disclose single production modules with polygonal horizontal footprints, and examples of how they can be arranged in clusters.

[0069] FIG. 7 discloses a cluster of production modules comprising different types of production modules.

[0070] FIG. 8 discloses how clusters of production modules can be linked to form macrostructures.

[0071] FIG. 9 discloses a macrostructure comprising a plurality of triangular clusters of production modules.

[0072] FIG. 10 discloses stationary and ambulatory clusters of production modules that are deployed across a stretch of water.

[0073] FIG. 11a discloses a marine production facility established around a rectangular cluster of production modules.

[0074] FIG. 11b discloses a perspective view of a production facility.

[0075] FIGS. 12a and 12b disclose a freestanding and a floating hexagonal cluster of production modules where growth surfaces are surrounded by a perimeter wall.

[0076] FIG. 12c discloses a combined sediment trap and biofilter.

[0077] FIGS. 13a and 13b disclose a triangular cluster of production modules where one side is closed by a perimeter wall.

[0078] FIG. 14 discloses a rosette-like enclosed macrostructure comprising triangular clusters of production modules with closed perimeter walls oriented outwards.

[0079] FIG. 15 discloses a linear macrostructure comprising triangular clusters of production modules with closed perimeter walls oriented outwards.

[0080] FIG. 16a discloses a marine production facility established around a rectangular cluster of production modules, where the facility can be closed off from the surrounding masses of water by a curtain-like barrier.

[0081] FIG. 16b discloses a perspective view of the facility in FIG. 16a.

[0082] FIG. 17 discloses a vertical cut view of a macrostructure comprising various types of linked production modules enclosing four fish farming ponds.

[0083] FIG. 18 discloses a vertical cut view of multiple macrostructures comprising various types of linked production modules in combination with fish farming tanks and agricultural areas.

[0084]

TABLE-US-00001 List of used reference numbers Number Designation 1 Upper part 2 Lower part 3 Mounting fixture 4 Take-up fixture 5 Retaining fixture 5b Weight 6 Retaining fixture 7 Growth surface 8 Cable 9 Attachment gear 10 Production module volume 11 Tank 12 Suspension cable 13 Sectioned growth surface 14 Helical strip 15 Vanes 16 Motor/windmill 17 Upper floor 18 Lower floor 19 Pillar 20 Sub-floor 21 Roof structure 22 Curtain 23 Tending/harvesting machine 24 Cylindrical enclosure 25 Closed wall 26 Water inlet tube 27 Collection surface 28 Separation and pumping device 29 Tube 30 Collection tank 31 Tube

DETAILED DESCRIPTION OF THE INVENTION WITH REFERENCE TO THE FIGURES

[0085] The marine bioproduction facility is centered around production modules where each is adapted to be arranged within a vertical column with a pre-defined horizontal cross section and extending downwards from the water surface. Each production module may be dedicated to one of a wide range of activities related to the overall running of the production facility.

[0086] In the case of farming of sessile organisms, the production module typically comprises a buoyant upper part at the water surface and optionally a submerged lower part of comparable size and shape at the bottom of the water column. Within this water column, there are disposed growth surfaces, typically in the form of sheets, ribbons, tubes, plates, meshes, nets, ropes or cables, on which sessile plants or animals can settle and grow. Each growth surface is suspended from the upper part of the production module in such a way that it provides easy access from above for tending and harvesting of the growth surface below and avoids entanglement with growth surfaces in neighboring production modules.

[0087] Examples of how this is achieved according to the present invention are shown in FIGS. 1a-f: The growth surfaces are suspended between a mounting fixture on the upper part and a guiding device on the lower part. The upper and lower parts are in the form of annuli (1), (2), each provided with fixtures for the attachment, deployment, manipulation and recovery of growth surfaces and associated suspension components and devices that are positioned between the upper and lower parts.

[0088] Mounting fixtures, suspension components (i.e. fixture and suspension means) and growth surfaces may take many forms. In order to facilitate understanding of the operational description to follow, the simple configurations shown in FIGS. 1a-f shall now be described in more detail.

[0089] In FIGS. 1a,b the growth surfaces are shown in the form of a longitudinal flat sheet (7) stretched between the fixtures on the upper and lower parts by means of a set of cables (8) and attachment gear (9). The cables are used for deploying and retrieving the growth surfaces through the opening in the upper part, and during the growth cycle they keep the growth surface in position within the volume occupied by the production module, indicated by the stippled lines (10). Spanning the annular upper part (1) is a first mounting fixture (3) from which the growth surface (7) is suspended via a cable (not visible in the figures) and attachment gear (9). The growth surface is connected at the lower end to a cable (8) which passes via a retaining fixture (5), (6) on the submerged lower part (2) and returns to a take-up fixture (4) on the upper part (1). Being located at water depths that may reach 20-50 m. and more, the retaining fixtures (5), (6) must be fail safe, and two simple designs are illustrated in FIGS. 1a,b: In FIG. 1a, the retaining fixture is a shaped crossbar (5) which the cable (8) loops around as shown. In FIG. 1b, the cable is guided across rollers (6). Other possible retaining fixtures shall be, e.g. a smooth tube or chute. In many marine environments, strategies must be adopted to tackle perturbations in the form of wave and tide motion. This may involve transient partial buckling of growth surfaces and active take-up of slack in the mounting fixtures at the upper part and/or at the bottom part. Many mounting variants are possible within the basic suspension mode shown in FIGS. 1a,b. For clarity, a single production module similar to the one shown in FIG. 1b is shown in FIG. 2, without reference numbering.

[0090] In FIG. 1c, the growth surface (7) has a cylindrical shape, typically being a thick rope or cable. The growth surface (7) is connected at the lower end to a cable (8) which passes via a retaining fixture (5) on the submerged lower part (2) and returns to a take-up fixture (4) on the upper part (1). When two elements are described as being connected, this may refer to a direct connection or a connection via a connecting element, and a cable as a connecting element should be broadly interpreted as an elongated member fitted for the connection purpose.

[0091] Slender growth surfaces in the form of ropes or cables allow more than one growth surface to be accommodated in a single production module. In FIG. 1d, 3 growth surfaces (7) are stretched between a first mounting fixture (3) on the upper part (1) and a retaining fixture (5) with three guiding rings on the lower part (2). Each growth surface is connected at its lower end to a cable (8) which runs through a guiding ring on the lower part (2) and up to a take-up fixture (4) on the upper part. There exist alternative embodiments when it comes to the numbers of growth surfaces and geometric arrangements illustrated in FIG. 1d.

[0092] In FIG. 1e, the growth surface (7), here shown as a rope, is suspended from a combined pay-out and take-up fixture (3) on the upper part, being kept extended by a weight (5b). This has the advantage of simplicity, but may in certain cases be less than optimal due to the cumulative burden on the flotation part of the facility and the danger of entanglement in facilities with a dense distribution of growth surfaces. One strategy to avoid entanglement is to use the lower part (2) as a separation device, where the growth surface (7) and weight (5b) are passed through the lower part and extends below it as illustrated in FIG. 1d.

[0093] FIG. 1f illustrates a simplified version of the arrangement shown in FIG. 1e, where there is no lower part to guide the suspended growth surface (7). Such arrangements are particularly relevant in situations where there is little or no water flow, e.g. in tanks or protected habitats, or where the growth surfaces are short compared to their nearest neighbor spacing.

[0094] The growth surfaces are typically in the form of a ribbon, sheet, cable, rope, web, net or tube, with a width less than the opening in the upper part and a length of up to several tens of meters. The growth surfaces are specifically adapted to accommodate sessile organisms such as tunicates which attach permanently to the growth surface early in their life cycles and grow from nutrients picked up from the surrounding water, which may either be open volumes in natural bodies of water or enclosed volumes in tanks or other enclosures. Such organisms include a wide variety of species, including tunicates, mussels, clams, barnacles, sponges, hydra and corals as well as macroalgae and seagrass. The growth surfaces may be segmented or be given different geometries along their length to accommodate different species of sessile organisms at different depths, and/or to present specific hydrodynamic properties in the water. Thus, they may be shaped and mounted so as to flutter or rotate in response to water flowing past, to increase exposure to nutrients. Conversely, they may cause water to be transported, e.g. in an upwelling fashion, when the growth surfaces are subjected to forced motion, e.g. rotation, from a motor attached to the mounting fixtures or by mechanical vanes and propellers driven by winds or water currents.

[0095] A complete growth and harvesting cycle for sessile organisms which settle naturally from the surrounding water volume (e.g. tunicates) shall typically proceed as illustrated in FIGS. 3a-e: FIG. 3a shows a production module similar to that shown in FIG. 1a in readiness before the cycle is initiated: A cable (8) passes from the mounting fixture (3) on the upper part (1) and down to the retaining fixture (5) on the lower part (2) where it loops back to the take-up fixture (4). In FIG. 3b the cable (8) has been connected to the bottom end of a growth substrate (7) which is being fed down into the water from a tending/harvesting machine (11) while the cable is pulled up at the take-up fixture (4). FIG. 3c shows the normal growth situation where the growth surface (7) is extended between the upper and lower parts (1), (2), being kept suitably taut and in position by the mounting and take-up fixtures (3), (4). FIG. 3d shows the situation in the harvesting phase: The growth surface (7) has been released from the mounting fixture (3) and is drawn out of the water and into the tending/harvesting machine (23), while cable is being paid out by the take-up fixture (4). The tending/harvesting machine (23) clears the biomass from the substrate and cleans it. In FIG. 3e the growth surface (7) is returned down into the water, assisted by coordinated pulling on the cable at the take-up fixture (4). Once in place as illustrated in FIG. 3c, a new growth cycle can begin. As an alternative to using cleaned substrates that are seeded opportunistically by larvae in the water volume surrounding the production module, it is also possible to incubate the growth surface in a separate controlled environment, before being returned into the production module as shown in FIG. 3e.

[0096] In practical farming facilities, a plurality of production modules are arranged side by side in a dense packing pattern, termed a cluster in the following. FIG. 4 shows a cluster in the form of a linear array comprising 6 production modules of the type shown in FIG. 2, with upper (1) and lower (2) parts and a tending/harvesting machine (23) in the process of lowering a growth surface (7), cf. the process stage illustrated in FIG. 3b.

[0097] More generally, production modules are assembled in two dimensional clusters, as exemplified in FIG. 5 and FIGS. 6a-d where clusters are formed by arranging individual production modules in close packed patterns. FIG. 5 shows a preferred embodiment in the form of a triangular cluster with a floor of buoyant upper parts (1) at the surface, mirrored by a floor of lower parts (2) below and with growth surfaces (7) suspended between them. The upper and lower floors are framed into a triangular shape where the annular upper and lower parts of each production module are packed in a hexagonal close packed (HCP) arrangement. FIGS. 6a-c show top views of polygon shaped production modules (left side in figures) and examples of cluster arrangements (right side in figures). Other shapes and cluster arrangements are possible.

[0098] The basic concept of production modules occupying specific water columns shall also include production modules with other functionalities than presenting growth surfaces to sessile organisms, e.g. storage tanks and technical service equipment. FIG. 7 shows a cluster of production modules of different types in a side view. Each production module occupies an allocated volume in the water indicated by the stippled lines (10) in FIG. 7. In addition to production modules that are open to the water and contain growth surfaces (7) suspended between a buoyant upper part (1) and a submerged lower part (2), there are production modules in the form of tanks (11) that are closed to the surrounding water volume. The tanks extend into the water as shown in FIG. 7 and may in principle be of any length. In many cases suspension cables (12) linking buoyant parts at the surface and submerged parts below may be included in the cluster to stabilize the overall structure.

[0099] Examples of production modules in the form of closed tanks include the following: [0100] Containment: The organisms being grown are freely moving or drifting in the water, e.g. larvae or micro-algae, and need to be restricted within a given volume, [0101] Incubation: The volumes inside the tanks provide a controlled and protected environment where organisms in early stages of development can be seeded and nurtured in preparation for being transferred to various production volumes in the facility or elsewhere.

[0102] Storage vessels. These are tanks that contain feedstock for the bioproduction, chemical additives to feedstock, temporary storage of harvested biomaterial, and industrial chemicals for machinery and technical installations in the production facility. [0103] Energy modules: Energy may be produced and stored as well as consumed in the production facility, requiring storage volumes for liquids and gases. Thus, closed compartments may be dedicated to the storage of fuel and compressed air. [0104] Tanks for buoyancy and ballasting control of the production facility or parts of it.

[0105] Certain essential features and advantages of the present invention can be discerned by inspection of FIG. 5 and FIGS. 6a-c: [0106] Each production module can be accessed and operated individually, without disturbing the others. This implies that production modules can be added to or removed from clusters, and organisms at different development stages can be farmed in neighboring production modules. Thus, by moving systematically across the array according to a predefined time schedule, it becomes possible to achieve continuous farming where seeded growth surfaces are deployed and mature growth surfaces are harvested in parallel operations. Another option is parallel multiculture farming, where different production modules carry different species, or a single production module carries different species on growth surfaces that are sectioned according to depth in the water column, cf. the sectioned growth surfaces (13) in FIG. 7. In some production modules, growth surfaces may be given special geometries in order to perform other tasks in addition to hosting sessile organisms: In FIG. 7 is shown a growth surface formed as a helical strip (14). When the strip is rotated about a vertical axis, water will be propelled upwards or downwards, depending on the direction of rotation, causing upwelling or downwelling in the local environment within the cluster. The rotation may be driven by water currents via vanes (15) attached to the strip, or from the top by means of a motor or windmill (16). [0107] Each production module in a cluster can be assigned a unique address. This makes it possible to tailor and optimize farming operations for each production module and to employ robots and sensors in a highly automated environment. [0108] A cluster of production modules may be given any shape, provided it is compatible with packing of the individual production modules side by side. When production modules are arranged in hexagonal close packed arrangements, the natural outline shapes of the clusters shall have trigonal or hexagonal symmetries as illustrated in FIG. 5 and FIGS. 6a-c, but other geometries are possible, e.g. linear as in FIG. 4, circular, etc. An important consequence of the mutually independent nature of individual production modules is scalability: This implies that production modules can be simply added to or removed from a given cluster, and clusters of standardized size and shape such as the triangles shown in FIG. 5 can be linked to other clusters to create macroscale structures, cf. FIG. 8 and FIG. 9. A cluster of production modules may constitute a mobile, self contained facility which can be moved from one locale to another and tethered there, or function as a roving production platform, cf. FIG. 10.

[0109] FIGS. 11a,b show an example of a more complex production facility where the growth surfaces (7) extend between rectangular clusters of upper parts (1) and lower parts (2) that constitute an upper floor (17) floating on the surface and a lower floor (18) directly below, tethered via 4 pillars (19). The facility includes a sub-floor (20) and a roof structure (21): The sub-floor (20) is indicated by the stippled rectangle in FIG. 11a and is shown in a side view in FIG. 11b. It is typically supported by the pillars surrounding the facility, either as a stiff structure fixed to the pillars or as a suspended sheet anchored on the pillars. In certain cases, the sub-floor may be positioned directly on the sea floor. Typical functions of the sub-floor are: [0110] Collect waste products from the production volume above as well as biomass that is lost from growth substrates during the growth period and during harvesting. [0111] Provide a habitat for bottom-living organisms that feed off the waste products from the production volume above. [0112] Increase the overall structural strength of the entire facility.

[0113] The roof structure (21) is indicated by the stippled rectangle in FIG. 11a and is shown in a side view in FIG. 11b. When installed, it is carried by the pillars or walls surrounding the production facility, but it may alternatively be mounted onto and supported by the platform itself. The roof can have many functions: [0114] Protecting the working environment on the production facility against sun, rain and snow. [0115] Providing a platform for technical installations, e.g. solar panels as shown in FIG. 11b. [0116] Providing areas for growing light-dependent cultures such as algae.

[0117] In many cases, it is desirable to include a perimeter structure around a cluster of production modules. This may be for improving the structural integrity of the bioproduction facility as well as for enclosing a volume of water. In FIGS. 12a,b are shown perspective views of a freestanding and a floating hexagonal cluster of production modules where an internal volume containing growth surfaces are surrounded by a perimeter wall consisting of closed cylindrical tanks (11) positioned side by side. This enables complete control of the environment within the facility, avoids cross contamination between the water inside and outside, and protects the interior from wave action. In certain cases involving light-averse organisms, a light tight cover may be attached across the top of the cluster.

[0118] FIG. 12c shows a combined sediment trap and biofilter for particulates: A closed wall perimeter structure (25) surrounds a cluster of production modules of two types: In the first type each production module contains a growth surface (7) loaded with sessile filter-feeding organisms, stretched out between the upper (1) and lower (2) parts of the production module. In the second type, each production module contains a collection tank (30). Water with fractions of coarse and fine particles enters through an inlet tube (26) and spreads throughout the enclosed volume. The coarse fractions of the particulates sediment quickly and are collected by a funnel-shaped collection surface (27), e.g. a plastic sheet, which surrounds the bottom of the enclosed volume as shown. The finer fractions of particulates sediment slowly and float in the water through the volume occupied by the growth surfaces, where they are fed upon by the filtering organisms. Fecal matter produced by the filtering organisms sediment to the bottom of the enclosed volume and is collected by the collection surface (27). Sediments near the collection surface are transported by gravity and water flow towards the funnel at the bottom, which feeds into a separation and pumping device (28). Concentrated particulates are pumped via a tube (29) into a collection tank (30) for further processing, while purified water is directed through another tube (31). The system shown in FIG. 12c can be employed in water purification, and the collected sediments may represent significant bioresources in addition to the biomass obtained by harvesting the organisms on the growth surfaces (7).

[0119] FIGS. 13a,b show a triangular cluster where one side is closed to the surrounding water volume by a wall of closed production modules in the shape of cylindrical tanks (11). Alternative ways of closing one side of the triangle include barrier sheets or curtains mounted between corner pillars (cf. pillars shown in FIG. 12), etc. Such clusters may be combined in a variety of ways to form larger scale facilities with extended perimeter structures that constitute barriers against water exchange. An example is shown in FIG. 14, where six triangular clusters are arranged in a rosette-like macrostructure with tanks (11) forming the closed walls in the triangular clusters facing outwards to form an enclosing barrier around the perimeter. In FIG. 15, similar triangular clusters are linked to form a linear macrostructure with a communicating volume enclosed by a wall of tanks (11) on either side: The macrostructure presents a barrier wall in the direction perpendicular to its length dimension, and an internal flowpath along its length. Clusters of similar or different shapes and sizes can be employed according to the same principle to create macrostructures with watercourses for guiding and controlling flows of nutrients and waste.

[0120] Another example of enclosing the bioproduction facility is shown in FIGS. 16a,b: Here, the whole water volume between the pillars (19) can be closed off from the surrounding masses of water by drawing a curtain (22) between each pair of pillars, extending from the lower floor (18) or the sub-floor (20) and to a point above the waterline. In FIG. 16a the curtains (22) are drawn in a horizontal direction to effect closure or opening. Partial enclosure is achieved when curtains are drawn vertically from the sub-floor and to a point below the waterline. This allows the upper strata of the production volume in the facility to be exposed to the surrounding water volume while avoiding disturbing the habitat on the sub-floor.

[0121] The modular concept of the present invention lends itself well to the construction of very large scale macrostructures where basic modules in the form of open or closed production modules and walls are linked across stretches of water and into the depths below to form three dimensional habitats and production facilities. FIG. 17 shows an example of a complex production facility where an enclosed fish farming space is surrounded by macroscale cluster structures forming upper (17) and lower (18) floors with suspended growth surfaces (7) between them. FIG. 18 shows a large scale combined facility where fish are farmed in cylindrical enclosures (24) and where the volume of water between the cylindrical enclosures is filled with growth substrates (7) stretched between an upper floor (17) of surface floating parts (1) and a lower floor (18) of lower parts (2). The area on top is dedicated to agriculture. By extension, it is clear that floating production facilities of any shape and size can be realized employing principles and basic modules as per the present invention.